Sewage disposal system with reusable flush medium

ABSTRACT

A sewage disposal system comprising a flush medium separation and distribution sub-system and a final sewage disposal subsystem. The disposal system is connected directly to existing plumbing. Sewage is transmitted from commodes and the like to a separation tank where the sewage is separated from the flush medium. A reusable flush medium replaces water to facilitate the separation process. The sewage is transferred to the final disposal sub-system and the flush medium is re-cycled for reuse.

United States Patent Claunch SEWAGE DISPOSAL SYSTEM WITH REUSABLE FLUSHMEDIUM Inventor: Robert W. Claunch, New Orleans, La.

Assignee:

Mich.

Dec. 21, 1970 Filed:

Appl. No.:

US. Cl ..4/10, 4/77, 4/90, 4/131, 210/152, 210/167 Int. Cl. ..E03d 3/00,E03d 5/014, E03d 5/016, E03d 5/10 Field oiSearch ..4/8,910, 114-118,4/131, 79, 89, 90; 210/154, 167

References Cited UNITED STATES PATENTS 1,303,358 5/1919 Montgomery..4/l0 X 2,724,837 11/1955 McPherson..... 2,858,939 11/1958 Corliss..4/10 X Chrysler Corporation, Highland Park, I

[ 1 July 4, 1972 3,079,612 3/1963 3,379,311 4/1968 3,431,563 3/1969Rascor ..4/l 3,538,517 11/1970 Cornish et al ..4/l0 3,579,646 5/1971Lekberg 3,597,769 8/1971 Brainard et al. 3,032,776 5/1962 Obert et a1...4/131 X Primary Examiner-Henry K. Artis Attorney-Talburtt & Baldwin [57] ABSTRACT A sewage disposal system comprising a flush mediumseparation and distribution sub-system and a final sewage disposalsub-system. The disposal system is connected directly to existingplumbing. Sewage istransmitted from commodes and the like to aseparation tank where the sewage is separated from the flush medium. Areusable flush medium replaces water to facilitate the separationprocess. The sewage is transferred to the final disposal sub-system andthe flush medium is re-cycled for re-use.

23 Claims, 3 Drawing Figures July4, 1972 United States Patent Claunch MW H y 7 L? /W MALL L E r g 7 l I l l l l I 1 l|1: 4 4,, 1 m I l 1 1| fiI M g 9 2 WM .unvw J T a m? 1.} $2 I f) .n W T l W M w E (Q gm T L c L Fw w I: nil. wn mmi w //M% SEWAGE DISPOSAL SYSTEM WITH REUSABLE FLUSHMEDIUM BACKGROUND OF THE INVENTION In the conventional sewage treatmentdisposal system the flush medium is water and represents 90 to 98percent of the total volume of the sewage. If a reusable flush medium isused which permits separation of the sewage wastes from the flush mediuma more compact and efficient sewage disposal system results. When theterm sewage is used herein, it is meant to include any of the typicalforms of sewage generally encountered including human excreta, paper,cigarette butts and the like.

Systems with reusable flush medium have been previously proposed whereinthe flush medium is of a density different than that of the sewage, thesewage being for the most part water. However, none of these priorproposals have, insofar as is presently known, been successfullydeveloped for actual practical use.

SUMMARY OF THE INVENTION This invention provides a practical system andapparatus for disposing of sewage while eliminating the use of water asa flush medium and substituting a reusable medium therefor. Toaccomplish this objective, the flush medium selected must besubstantially immiscible with water, of a sufficient difference indensity from that of water and sewage to permit physical separation ofthe sewage from the flush medium and it must be chemically stable at theoperating conditions of the sewage facility and in the presence ofsewage.

It is a primary objective of the invention to provide a practicalapparatus and system for flush medium collection and to achievesubstantially complete separation of the flush medium from the sewage bya simple and inexpensive means.

To accomplish these and other objectives the flush medium is recycledthrough a fluid circulation means to a point of use, such as a commode,then flushed with sewage through a sewer line into a separating tank,where the flush medium is separated from the sewage and returned to thefluid circulation means. The sewage, which in most cases'will consist ofhuman excreta and other nonnal'commode or urinal deposits as previouslystated, may be received in a standard toilet bowl from which it isflushed with the flush medium to the separating tank where the sewage istransferred after separation from the flush medium to a point ofultimate sewage disposal such as an incinerator, aerobic digestor oreven simply to a holding tank or any other suitable means.

More specifically, the preferred system transfers sewage to acombination sump and flush medium storage and separation tank whereinseparation of the flush medium from the sewage takes place. Sewagecarried by the flush medium enters the sump where the sewage, due to itsdifference in density, settles to the bottom of the sump while the flushmedium rises above the sewage and is thereby separated therefrom.

The sewage collects in the bottom of the sump until a suffcient quantityhas accumulated to activate an automatic transfer means such as a wastegrinder and a sump valve. Sewage then passes through the grinder andvalve into a sewage receiving means, such as a catch tank. After thesewage has been transferred the sump valve automatically closes and theaccumulation of sewage in the sump starts again. The sewage that hasbeen passed through the grinder is automatically transferred from thecatch tank to a point of ultimate disposal, such as an incinerator.

After the flush medium rises above the sewage in the combination sumpand storage tank, it passes through suitable filter means and into afluid circulation system which will preferably include a pressurizedstorage tank. Pressure switch means is used to automatically activate apump in the circulation system when the pressure drops below a pre-setminimum.

In the preferred embodiment of the invention the flush medium issupplied on a demand basis to the sewage system at BRIEF DESCRIPTION OFTHE DRAWING FIG. I is a schematic representation of a sewage disposalsystem and apparatus according to the present invention.

FIG. 2 is a pictorial functional representation of some of the basicfunctional control components for the system and apparatus.

FIG. 3 is an electrical schematic showing preferred control andoperating circuits for an automatic system and apparatus according tothe present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT A sewage disposal system andapparatus according to the invention is shown in FIG. 1 connected to acommode 10 which includes a water closet tank 12 for storing a supply offlush medium to be used in the commode. Tank 12 includes a valve (notshown) for controlling the flow of flush medium through the commode andthe sewage system as is well known in the prior art. The valve isoperated by a suitable means such as manually operated handle 14.Generally indicated at 16 is a separating tank connected to commode 10by means of a sewer line 18. Sewage enters separating tank 16 through alower or sump portion 20 which is separated from an upper or storageportion 22 by means of a screen 24 which is horizontally positionedtherebetween. Additional screen means 26 may also be arranged around theopening between the upper or lower portions of the tank as shown.

When the system is initially placed in operation, a fluid flush mediumhaving a density less than that of water is placed in the separatingtank 16. As will be described hereinbelow, the flush medium iscirculated through a flush medium circulation system to arrive at thecommode and is there used to carry sewage into sump 20 of separatingtank 16 via line 18. When the mixture of flush medium and sewage enterssump 20, the flush medium being of the lesser density tends to risethrough screen 24 and screen means 26 into upper portion 22 of tank 16thus separating itself from the sewage which remains in the lower su'rnpportion 20. In actual practice, the flush medium floats on top of thesewage.

Sewage transfer means including an electrically operated grinder ormacerator 28 of any of the types well known in the an and anelectrically operated sump valve 30 are connected by means of a sewerline to the bottom of sump 20. Sewage receiving means such as tank 32having an upper inlet 34 and a lower outlet 36 is connected to thesewage transfer means to receive sewage from tank 16.

Additional electrically operable sewage transfer means is connected tosewage receiving tank 32 at outlet 36 and includes an electricallyoperable pump 38 and another electrically operable valve 40 both ofwhich are connected to tank 32 by a suitable sewer line as shown. Acheck valve 42 is included in the line which, as shown, terminates at apoint of ultimate sewage disposal such as incinerator 44.

Since suitable types of electrically operable valves and pumps will beapparent to those familiar with this art, there is no need to describethese components in detail. Furthermore, the means for ultimate or finaldisposal of the separated sewage may take the form of any various meanssuch as thermal reduction by incinerators or the like, biologicaltreatment by aerobic digestors or the like, bulk storage in holdingtanks or any other suitable means.

The fluid circulation means for recirculating and using the reusableflush medium generally extends between the upper portion 22 ofseparating tank I6 and the point of ultimate use of the flush medium,which in this case is tank 12 and commode 10. As shown in FIG. 1, a line46 extending between upper portion 22 of separating tank 16 and commodetank 12 includes an electrically operable pump 48, a pressurized fluidreservoir means or accumulator 50, and a check valve 52. The accumulatoror pressurized fluid reservoir 50 is shown with a pressure gauge54 andan electrical pressure sensitive switch means 56 mounted thereon.Variousmeans for filtering the flush medium may be included in line 46.For example, a coalescere filter 58 is shown which in combination withscreen 24 and 26 will provide substantial filtering of the flush medium.Screen 24 may be 40 mesh while the screen in 26 may be 20 mesh. Acoalescere is a device or material which tends to accumulate tracequantities of water in the medium into large droplets which finallyattain a size that will cause the water drop to fall through the flushmedium to the bottom of the tank. A fiberglass insulation pad may beused for this purpose. It has the added advantage in that it tends tocollect particulate matter and therefore acts as a filter also.Additional filter means of various types may be included at variouspoints in line 46. Also, the flush medium is desirably furthermaintained by the periodic additions of biological agents thereto forgerm control. Various odor masking agents may also be periodicallyincluded and the fluid may even be colored by artificial agents ifdesired for psychological reasons.

Operation of the system is essentially automatic due to the variouslevel sensing means which are positioned in separating tank 16 andsewage receiving tank 32 and various-electrical circuit means includingboth control and operating circuits which inter-connect the electricallyoperable sewage transfer means and the like between separating tank 16and sewage receiving tank 32, between sewage receiving tank 32 and thepointof ultimate sewage disposal such as incinerator 44 and also in theflush medium circulation line 46.v

More specifically, level sensing means such as a float assembly.including float 60 operably connected to a normally open electricalswitch means 62 is positioned within sump 20 below screen 24. 'Whensewage is received in separating tank 16 float 60 is constructed and soarranged as to close switch means 62 at a predetermined level in thetank, such as a level which is co-extensive with the plane of screen 24.Float 60 may also be operably connected to a normally closed electricalswitch means 64, that when separating tank 16 is empty of sewage,although there may very well be fluid flush medium present therein, thefloat will open switch means 64. These ends are accomplished byproviding a float having a density which is heavier than that of theflush medium but lighter than that of the sewage'so it will float in thesewage but not in the flush medium. Such a float may be of a hollowmetal construction similar to the float used in a commode water tank.Ballast is added to the float rod such that the volume the floatdisplaces supports a weight equivalent to a volume of fluid with a meanspecific gravity of say approximately 0.95. Thus with a flush medium of0.85 specific gravity and the sewage at approximately 1.0 specificgravity, enough of the float will sink into the sewage phase so that theaverage specific gravity of the fluid displaced is 0.95.

A back-up sewage level sensing means such as another float assemblyincluding float 66 and normally open electrical switch means 68 is alsoincluded in separatingtank 16. However, it is positioned aboveseparating screen 24. Float 66 is of the same type as float 60 and willindicate, due to its position in the upper portion 22 of separating tank16 when it closes switch means 68, that sewage has risen in excess of apredetermined desirable level in separating tank 16. All of theelectricalswitch meansare arranged to'provide control inputs toelectrical circuit means which are described further'hereinbelow. 1

Additional level sensing means which ispositioned in sewagereceivingtank 32, may also take the form of additional float assemblies. Morespecifically, float 70 operably connected to normally closed electricalswitch means 72 is positioned in an upper portion of sewage receivingtank 32,

preferably on a level which is essentially the same as inlet 34, tosignify filling of sewage receiving tank 32 with sewage and to provide acontrol input into a control circuit connected to the switch means 72 asis described hereinbelow. Another float assembly including float 74operably connected to a normally open electrical switch means 76 is alsoincluded in sewage receiving tank 32. Float 74 is positioned near thebottom of tank 32 and is arranged to close normally open switch means 76when the tank is emptied to a predetermined level near the bottomthereof.

Reference is now made to FIG. 2 for a brief description of the variouscontrol and operational inter-relationship of the system and apparatusaccording to the present invention. FIG. 2 shows that switch means 62and 68, which are operated by floats 60 and 66 respectively, and switchmeans 72, which is operated by float 70 control the operation of grinder28 and sump valve 30 thereby transferring sewage from sump 20 to sewagereceiving tank 32. Pump 38 and .valve 40 are also operated at this time.Once operated, pump 38 and valve 40 are controlled by switch means 76,which is operated by float 74, thereby transferring sewage from tank 32.Also, pressure sensitive switch 56 and accumulator 50 are arranged toactivate electrically operable pump 48 and maintain pressure in line 46at a predetermined level, such as at 40 psi, as indicated in FIG. 2. I

With the above in mind, the operation of the system may be describedgenerally as follows. Waste products and flush medium are transferredfrom commode 10 to sump 20 through common sewer line 18. When themixture enters sump 20, sewage products sink to the bottom thereof andthe flush medium rises from sump 20 through coarse screen 24- into theseparation and storage section or upper portion 22 of separating tank16. Sewage products continue to collect in sump 20 until a sufficientquantity causes float 60 to actuate switch means 62 starting grinder 28and opening electrically operable sump valve 30. The sewage then passesthrough grinder 28 and valve 30 into sewage receiving tank 32. When thesewage receiving tank is full float 70 actuates switch. means 72which-stops the grinder and closes the electrically operated valve 30. Aback-up to the closing of the valve is provided by float 60 and switchmeans 64.

At the same time grinder 28 and sump valve 30 operate, pump 38 willoperate and electrically operable valve 40 will open. Pump 38 thenremoves sewage from the sewage receiving means and delivers it to theultimate point of waste disposal such as incinerator 44. After thesewage products are removed from tank 32, float 74 returns to its normallow position causing switch means 76 to assume its nonnally opencondition thereby terminating operation of pump 38- and closingelectrically operable valve 40. It can be seen that separation of thesewage from the flush medium and transfer of the sewage without thesubstantial loss of flush medium from the system is accomplished by theapparatus and controls described above.

The flush medium upon rising into upper portion 22 of separating tank16, passes through screen filter 26 which is intended to removesuspended water and solids from the medium. Float 66 and switch means 68located in upper portion 22 of tank 16 and above screen 24 function as aback-up level sensing means to float 60 and switch means 62 as will bedescribed in detail in connection with FIG. 3. However, this floatassembly will open sump valve 30 and operate grinder 28 when the sewagelevel rises above screen 24. Flush medium is stored in upper portion 22of tank 16 until a demand is established in the pressurized portion ofthe circulation system, such as by the flushing of commode 10. The flushmedium flows to the suction side of pump 48 where it is Reference ismade to FIG. 3 which shows a preferred arrangement in detail by whichthe sewage disposal system may be automatically controlled. For purposesof explanation and convenience in diagraming, the schematic circuits ofFIG. 3 are shown broken into various sub-circuits indicated by the areasenclosed by dotted lines and numbers 80, 82, 84 and 86 respectively.

Electrical circuit means 80 is preferably connected across a 24 voltD.C. power supply. As shown, it includes switches 62 and 68 connected inparallel with respect to each other, both being serially connected toswitch 72 and a relay indicated at A, which preferably includes a timedelay such as a one minute time delay. Relay A is provided with a firstset of normally open contacts A-l in sub-circuit 80 and a second set ofnormally open contacts A-2 in sub-circuit 84. A diode 78 may be includedbetween relay A and switch 62 as shown. Alarm and failure modes areincluded in sub-circuit 80 and are controlled by relay contacts G-2which are operated by relay G of sub-circuit 82. Relay G is alsoconnected to a 24 volt D.C. power source and preferably includes a timedelay such as a 20 second time delay. Relay contacts G-l are connectedin series between the positive side of the 24 volt D.C. source andswitch 72 while contacts G- 2 are connected between the positive side ofthe 24 volt D.C. source and a point intermediate relay .1 and thenormally open contacts J-l thereof via the common terminals indicated atCT. Relay J is arranged as shown to control the operation of an alarm 80and a light 82 when contacts G-2 close indicating that separating tank16 is empty. Relay H and its normally open contacts H-l are operablyconnected to switch 68 via a line including diode 84. Relay H anditscontacts H-l are arranged to operate alarm 80 and an alarm light 86to indicate that separating tank 16 is over-filling with sewage. Bothrelays J and H are connected through a re-set switch 88 to the 24 voltD.C. power source such that once they are energized they will remain inthat condition until the re-set switch 88 is momentarily opened.

Sub-circuit 84 includes 5 control relays B, C, D, E, and F respectivelywhich are connected in parallel to relay contacts A-2. Relays B and Care separated from relays D, E and F by a diode 90 for circuit isolationpurposes. Relay B is arranged with contacts B-l, B-2 and B-3, connectedinto a 100 volt three phase A.C. power line to control the operation ofgrinder 28. Relay C is arranged with its contacts C-l in a l volt singlephase A.C. power line to control the operation of electrically operablevalve 30. Relay D is arranged with its contacts D-l in a 1 15 voltsingle phase A.C. line to control the operation of electrically operablepump 38. Relay E is arranged withits contacts E-l in a 115 volt singlephase A.C. power line to control the operation of valve 40. Relay F isarranged in series circuit with switch 76 while its contacts F-l arepositioned intermediate switch 76 and the positive side of the 24 voltD.C. control power source as shown.

In sub-circuit 86, pressure switch 56 is connected intermediate thepositive side of the 24 volt D.C. power source and relay K. Relay K isarranged with its contacts K-l, K-2 and K-3 connected into a 100 voltthree phase AC. power line which controls the operation of pump 48.

An operating cycle is normally initiated by the closing of switch 62 inseparating tank 16 by float 60 when sewage rises to a predeterminedlevel in sump 20. Switch 62 applies the 24 volt D.C. power source torelay A if switch 72 is not operated. Relay A as noted hereinbefore is atime delay relay, preferably approximately 1 minute, which thus will notoperate during sporadic surges caused by flushing. Once relay A isoperated it is locked through its own contacts A-l until switch 72 opensin response to the upward movement of float 70 in sewage receiving tank72 indicating that sewage receiving tank 32 is full.

Redundant switches 64 and 68 are provided in case of failure of switches62 and 72. Should switch 62 fail to function, switch 68 will close andinitiate the cycle by energizing relay A and closing contacts A-1 andA-2. Should switch 72 fail to function, switch 64, which is open as longas there is sewage and/or flush medium in separating tank 16 will closeand operate relay G thus causing normally closed contacts G-l to openand normally open contacts G-2 to close. This will release relay Apreventing the loss of any flush medium and will energize relay Jcausing alarm to be activated and light 82 to be lit. Relay G as notedhereinabove is a time delay relay, preferably approximately 20 seconds,so it will not operate when float 66 is momentarily forced down duringthe normal emptying of separating tank 16. Relay H is energized whenswitch 68 closes through diode 84 to activate alarm 80 and light 86 thusindicating that separating tank 16 is overfilling with sewage. Diode 84isolates the alarm circuit portion of 80 from the remainder thereof asshown so that switches 62, 72, 64 and 68 along with relay A are isolatedfrom the 24 volt D.C. power applied through re-set switch 88 to relays Hand J when the alarm condition exists.

When operation of the system is initiated, relay A operates grinder 28via relay B; it operates valve 30 via relay C; it operates pump 38 viarelay D, and it operates valve 40 via relay E. Grinder 28 and valve 30remain in operation until relay A releases contacts A 2. However, pump38 and valve 40 will lock-in" through relay F and its contacts F-l whenswitch 76 closes as tank 32 starts to fill causing float 74 to rise.Pump 38 and valve 40 remain in operation until sewage receiving tank 32empties and switch .76 opens due to the falling of float 74.

The flush medium is circulated through the system by pump 48 which iscontrolled by pressure switch 56. When the system pressure falls to apredetermined pressure level switch 56 closes operating relay K andapplying power to pump 48 via contacts K-l, K-2 and K-3. Whenthepressure in the system reaches a higher predetermined pressure thepressure switch 56 opens and pump 48 is turned off. An example of thepredetermined upper and lower pressures and the pressure range has beenfound useful in connection with this system, is the range of 20 to 40psi.

In general, any flush medium selected for use with the system accordingto this invention will be substantially immiscible with water and of asufficient difference in density or specific gravity from that of waterto permit physical separation of the sewage from the flush medium by thesettling process. The flush medium will also be chemically stable at theoperating conditions of the sewagedisposal apparatus and in the presenceof human waste and other sewage. Further characteristics of the mediumare that it have flow characteristics suitable for flushing andtransporting sewage, that it not produce a toxic or fire hazard and thatit be esthetically acceptable in color and odor.

Some fluids which have proven to be acceptable are the TABLE SpecificFlash Fluid Gravity Point Viscosity DlALA Ax 0.865 300F 10 CS at 77F DC20010 CS 0.934 325'! 10 CS at 77F 20 CS 0.949 450F 20 CS at 77F 50 CS0.960 545F 50 CS at 77F MCS 996 0.922 385F 8.22 CS at F MCS 997 0.914450F 14.5 CS at 100F As previously indicated, the flush medium may becolor marked with several attendant advantages in that color componentsdue to urinary pigments which tend to be abstracted into the fluidmedium are hidden and better visual accessment of fluid mediumseparation from the waste can be made. Such coloration can be impartedby oil soluble dyes which are available from textile dye manufacturersin a wide range of colors at reasonable" prices. Similarily, deodorizingperfumes can be incorporated into the fluid medium to provide a pleasingodor if necessary.

The preferred mineral oil base fluid medium contemplated for use withthis system is of itself incapable of providing support for bacteria orviruses. However, a certain level of entrainment at the interface of thefluid medium and the sewage in the separating tank is inevitable.Consequently, the incorporation of an oil soluble biocide is desirableto act as a scavenger for entrained contamination. Several such biocideshave been evaluated and found satisfactory for this purpose. Biobor J.F. which is manufactured by the US. Borax Company is a typical example.

Having described the invention, the embodiments thereof in which anexclusive property or right is claimed are defined as follows:

1. A sewage disposal .system for separating sewagefrom a flush medium sothe medium can be reused with minimal loss, comprising:

a non-aqueous liquid flush medium for receiving and carrying sewage, theflush medium having a specific gravity less than that of water;

a separating tank having an inlet in its lower portion for receivingsewage carried by the flush medium, the flush medium separating from thesewage after entering the separating tank and floating above the sewagedue to its different specific gravity, the sewage remaining in the lowerportion of the separating tank;

sewage receiving means for receiving sewage from the separatingtankafter its separation from the flush medielectrically operable sewagetransfer means connected to the lower portion of the separating tank fortransferring the sewage from the lower portion of the separating tank vto the sewage receiving means;

first electrical circuit means operably connected to the sewagetransfermeans for initiating its operation;

sewage level sensingvmeans positioned in the lower portion of theseparating tank and operably connected to the first electricalcircuitmeans for activating it when the sewage reaches a predetermined level inthe tank thereby initiating operation of the sewage transfer means andthe transfer of sewage from'the separating tank to the sewage,

receiving means;

second electrical circuit means operably connected to the sewagetransfer means for terminating its operation, and

sewage level sensing means positioned in the sewage receiving means andoperably connected to the second electrical circuit means forde-activating it when the sewage reaches a predetermined level in thesewage receiving means thereby terminating operation of the sewagetransfer means and the transfer of sewage from the separating tank tothe sewage receiving means.

2. The system according to claim 1 wherein the level sensing means inthe separating tank and in the sewage receiving means both consist offloat assemblies.

3. The system according to claim 1 wherein the sewage transfer meansincludes means for guiding the sewage and pump means for transferringit.

4, The system accordingto claim 1 wherein:

the separating tank includes a relatively coarse mesh screen positionedtherein, dividing the tank into upper and lower portions, and

the sewage level sensing means in the separating tank is positioned inthe lower portion thereof.

5. The system according to claim 4 wherein the sewagelevel sensing meansin theseparating tank includes two sensor assernblies, one beingpositioned below the screen while the other is positioned above thescreen, the lower assembly providing the primary operating function withrespect to the first electrical circuit means and the upper assemblybeing redundant with respect thereto.

6. The system according to claim I wherein:

the first electrical circuit means includes a normally open electricalswitch means operably connected to. the separating tank sewage levelsensing means to be closed thereby when the sewage reaches apredetermined level in the separating tank and initiates operation ofthe sewage transfer means, and

the second electrical circuit means includes a normally closedelectrical switch means connected in parallel with the normally openswitch means of the first circuit means and operably connected to thesewage receiving means sewage level sensing means to be opened therebywhen the sewage reaches a predetermined levelin the sewage receivingmeans and terminate operation of the sewage transfer means.

7. The system according to claim 6 wherein:

the. separating tank includes a screen positioned therein,

dividing the tank into upper and lower portions, and

the sewage level sensing means in the separating tank is positioned inthe lower portion thereof.

8. The system according to claim 7 wherein:

the sewage level sensing means in the separating tank includes twosensor assemblies, one being positioned below the screen while the otheris positioned above the screen, the lower assembly providing the primaryoperating function with respect to the first electrical circuit meansand the upper assembly being redundant with respect thereto.

9. The system according to claim 8 wherein the first and secondelectrical circuit means are serially connected to a source ofelectrical power and further include:

a relay having a winding connected serially to the normally open switchmeans, the relay also including a pair of normally open electricalcontacts which close when the relay winding is energized by the closingof the normally open switch, and

additional circuit means operably connecting the relay contacts to thesewagetransfer means. I

10. The system according to claim 9 wherein the sewage transfer meansincludes:

an electrical grinder and an electrically operated valve interconnectedbetween the separating tank and the sewage receiving means;

an outlet for sewage in the sewage receiving means;

an electrical pump and another electrically operable valve connectedinto the outlet, and

all of the above are operably connected electrically in parallel to therelay contacts whereby operation is initiated when the relay contactsclose.

11. The system according to claim 9 including:

an additional normally closed switch means operably connected to theseparating tank sewage level sensing means to open when the tank emptiesto a predetermined level;

a relay having a winding; two pairs of electrical contacts;

electrical circuit means connecting the relay winding to the switchmeans whereby the winding is normally energized, one set of contacts arenormally closed and the other set of contacts are normally open duringenergization of the winding;

electrical circuit means connecting the normally closed contacts of thenonnally energized winding in series circuit between the secondelectrical circuit means and its power sourcemeans;

an electrical alarm circuit, and

electrical circuit means connecting the normally open contacts of thenormallyenergized winding in series circuit with the alarm circuitwhereby power may be supplied to the alarm circuit when the contactsclose due to the opening of the normally closed switch means.

12. The system according to claim 8 wherein all the level sensing meansused comprise float assemblies arranged to mechanically operate theelectrical switch means.

13. The system according to claim 1 wherein the sewage transfer meanscomprises a grinder and an electrically operated valve, and conduitmeans is included to interconnect the grinder and valve between theseparating tank and the sewage receiving means.

14. The system according to claim 1 including:

additional electrically operable sewage transfer means connected to thesewage receiving means for transferring sewage therefrom to an ultimatepoint of disposal from the system;

additional electrical circuit means operably connecting the additionalsewage transfer means to the first electrical circuit means so that itsoperation is initiated when the first electrical circuit means isactivated;

further additional electrical circuit means operably connected to theadditional sewage transfer means for continuing its operation after thefirst electrical circuit means is de-activated, and

additional sewage level sensing means inthe sewage receiving meansoperably connected to the further additional electrical circuit meansfor de-activating it when the sewage receiving means has emptied to apredetermined level.

15. The system according to claim 14 wherein:

the additional electrically operable transfer means comprises pump andvalve means, and

conduit means connecting the pump and valve means to the sewagereceiving means near the bottom thereof.

16. The system according to claim 14 wherein the additional levelsensing means comprises a float assembly positioned to operate when thesewage receiving means empties to a predetermined level.

17. The system according to claim 14 wherein the additional electricalcircuit means comprises:

an electrical control circuit connected between the first electricalcircuit means and the additional sewage transfer means,

an asymmetric electrical conductor connected in the circuit so as toconduct current only from the first electrical circuit means to theadditional electrical circuit means;

normally open switch means closed by the additional sewage level sensingmeans when sewage reaches a predetermined level in the sewage receivingmeans;

a source of electrical energy and an electrical relay including anenergization coil and a pair of normally open electrical contactsconnected serially to the normally open switch means whereby theadditional electrically operable sewage transfer means is locked-in"operation after the first electrical circuit means is de-activated andmaintained in operation until the additional level sensing meansreleases the closed normally open switch means after the sewagereceiving means has emptied to a predetermined level.

18. The system according to claim 17 wherein the additional levelsensing means is a float positioned near the bottom of the sewagereceiving means and mechanically connected to the normally open switchmeans to close it when sewage rises in the sewage receiving meanscausing the float to rise above a normal rest position and to releasethe switch when the sewage level falls to a level corresponding to thenormal float position culation means; I a normally open pressureoperated electrical switch means is connected to the accumulator meansfor closing when the pressure therein falls below a predetermined value;electrical circuit means connecting the switch means to a source ofelectrical energy and to the pump means of the fluid circulation meanswhereby additional fluid is pumped from the separating tank into thefluid circulation means when the pressure therein falls below thepredetermined value maintained by the pressure switch means.

21. The system according to claim 20 including check valve meanspositioned in the fluid circulation means at a point between the pumpmeans and the accumulator means.

22. The system according to claim 19 including filter means positionedat the fluid entrance to the fluid circulation means and elsewheretherein for further separating sewage from the fluid before its reuse.

23. A sewage disposal system for separating sewage from a flush mediumso the medium can be reused with minimal loss, comprising:

a non-aqueous liquid flush medium for receiving and carrying sewage, theflush medium having a specific gravity less than that of water;

a separating tank having an inlet for receiving sewage carried by theflush medium, the flush medium separating from the sewage after enteringthe separating tank and floating above the sewage due to its differentspecific gravity, the sewage remaining in a lower portion of theseparating tank;

sewage receiving means for receiving sewage from the separating tankafter its separation from the flush medium;

sewage transfer means connected to the separating tank for transferringthe sewage from the separating tank to the sewage receiving means;

means operably connected to the sewage transfer means for initiating itsoperation, and

sewage level sensing means positioned in a lower portion of theseparating tank and operably connected to the means for activating itwhen the sewage reaches a predetermined level in the tank therebyinitiating operation of the sewage transfer means and the transfer ofsewage from the separating tank to the sewage receiving means.

Dated Patent No.

Inventor) Robert W. Claunch It is certified that error appears in theabove-identified patent and that said Letters Patent are herebycorrected as shown below:

Column 4, line 8, after "arranged to" the phrase "close normally open"should read open normally closed-.

line 19, cancel "normally".

Column 5, lines 42 and 57, "100 volt" should read ll5 volt-.

line 75, "there is" should read the-.

Column 6, line 1, the phrase "and/or flush medium" should read is belowthe minimum sewage level; same line, after the numeral "16" insert acomma Signed and Scaled this Twenty-sixth Day of October 1976 [SEAL]Arrest:

RUTH C. MASON C. MARSHALL DANN Arresting Officer Commissioner oj'Palenrsand Trademarks UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTIONPatent No. 3 673 a 614 Dated y 4 a 1972 lnventor(s) ROBERT w. CLAUNCl-IIt is certified that error appears in the above-identified patent andthat said Letters Patent are hereby corrected as shown below:

In the drawings, Sheet 1, Fig. '1, reference character 32, should beadded to designate the tank having an upper inlet 34 and a lower inlet36; Sheet 2, Fig. 3, "86" should be changed to-87 and "82" should 'bechanged to 83; "80" should be changed to 81 and "84" should be changedto 85.

Column 4, line 39, after "full", insert -a comma. Column 5 line 11 after"72", insert a comma; line ,28, "-80" should read '81 same 7 line "82"should read 83] line 31, "84" should read 85 line 32, "80" should read81 line 33, "86" should read 87 line 69, "72" should read 32 Column 6,line l, after "16",

insert a comma, line 5, "80" should read 81 line 6, "82" should read 83line 10, "84" should read 85. same line, "80" should read 81 line 11,"86" should read 87 line 12, "84" should read 85 line 36,

after "range", insert which "Column 7,-l'ine 1, after "ponents", inserta comma line 3, after "medium", insert 8. comma.

Signed and sealed this 13th day of August 1974.

( E Attest:

McCOY M. GIBSON, JR. C. MARSHALL 'DANN Attesting Officer Commissioner ofPatents 'ORM P0405) USCOMM-DC 60376-P6B a U. S. GOVERNINT PRINTINGOFFICE 7 l", O3'3Il,

1. A sewage disposal system for separating sewage from a flush medium sothe medium can be reused with minimal loss, comprising: a non-aqueousliquid flush mediUm for receiving and carrying sewage, the flush mediumhaving a specific gravity less than that of water; a separating tankhaving an inlet in its lower portion for receiving sewage carried by theflush medium, the flush medium separating from the sewage after enteringthe separating tank and floating above the sewage due to its differentspecific gravity, the sewage remaining in the lower portion of theseparating tank; sewage receiving means for receiving sewage from theseparating tank after its separation from the flush medium; electricallyoperable sewage transfer means connected to the lower portion of theseparating tank for transferring the sewage from the lower portion ofthe separating tank to the sewage receiving means; first electricalcircuit means operably connected to the sewage transfer means forinitiating its operation; sewage level sensing means positioned in thelower portion of the separating tank and operably connected to the firstelectrical circuit means for activating it when the sewage reaches apredetermined level in the tank thereby initiating operation of thesewage transfer means and the transfer of sewage from the separatingtank to the sewage receiving means; second electrical circuit meansoperably connected to the sewage transfer means for terminating itsoperation, and sewage level sensing means positioned in the sewagereceiving means and operably connected to the second electrical circuitmeans for de-activating it when the sewage reaches a predetermined levelin the sewage receiving means thereby terminating operation of thesewage transfer means and the transfer of sewage from the separatingtank to the sewage receiving means.
 2. The system according to claim 1wherein the level sensing means in the separating tank and in the sewagereceiving means both consist of float assemblies.
 3. The systemaccording to claim 1 wherein the sewage transfer means includes meansfor guiding the sewage and pump means for transferring it.
 4. The systemaccording to claim 1 wherein: the separating tank includes a relativelycoarse mesh screen positioned therein, dividing the tank into upper andlower portions, and the sewage level sensing means in the separatingtank is positioned in the lower portion thereof.
 5. The system accordingto claim 4 wherein the sewage level sensing means in the separating tankincludes two sensor assemblies, one being positioned below the screenwhile the other is positioned above the screen, the lower assemblyproviding the primary operating function with respect to the firstelectrical circuit means and the upper assembly being redundant withrespect thereto.
 6. The system according to claim 1 wherein: the firstelectrical circuit means includes a normally open electrical switchmeans operably connected to the separating tank sewage level sensingmeans to be closed thereby when the sewage reaches a predetermined levelin the separating tank and initiates operation of the sewage transfermeans, and the second electrical circuit means includes a normallyclosed electrical switch means connected in parallel with the normallyopen switch means of the first circuit means and operably connected tothe sewage receiving means sewage level sensing means to be openedthereby when the sewage reaches a predetermined level in the sewagereceiving means and terminate operation of the sewage transfer means. 7.The system according to claim 6 wherein: the separating tank includes ascreen positioned therein, dividing the tank into upper and lowerportions, and the sewage level sensing means in the separating tank ispositioned in the lower portion thereof.
 8. The system according toclaim 7 wherein: the sewage level sensing means in the separating tankincludes two sensor assemblies, one being positioned below the screenwhile the other is positioned above the screen, the lower assemblyproviding the primary operating function with respect to the firstelecTrical circuit means and the upper assembly being redundant withrespect thereto.
 9. The system according to claim 8 wherein the firstand second electrical circuit means are serially connected to a sourceof electrical power and further include: a relay having a windingconnected serially to the normally open switch means, the relay alsoincluding a pair of normally open electrical contacts which close whenthe relay winding is energized by the closing of the normally openswitch, and additional circuit means operably connecting the relaycontacts to the sewage transfer means.
 10. The system according to claim9 wherein the sewage transfer means includes: an electrical grinder andan electrically operated valve interconnected between the separatingtank and the sewage receiving means; an outlet for sewage in the sewagereceiving means; an electrical pump and another electrically operablevalve connected into the outlet, and all of the above are operablyconnected electrically in parallel to the relay contacts wherebyoperation is initiated when the relay contacts close.
 11. The systemaccording to claim 9 including: an additional normally closed switchmeans operably connected to the separating tank sewage level sensingmeans to open when the tank empties to a predetermined level; a relayhaving a winding; two pairs of electrical contacts; electrical circuitmeans connecting the relay winding to the switch means whereby thewinding is normally energized, one set of contacts are normally closedand the other set of contacts are normally open during energization ofthe winding; electrical circuit means connecting the normally closedcontacts of the normally energized winding in series circuit between thesecond electrical circuit means and its power source means; anelectrical alarm circuit, and electrical circuit means connecting thenormally open contacts of the normally energized winding in seriescircuit with the alarm circuit whereby power may be supplied to thealarm circuit when the contacts close due to the opening of the normallyclosed switch means.
 12. The system according to claim 8 wherein all thelevel sensing means used comprise float assemblies arranged tomechanically operate the electrical switch means.
 13. The systemaccording to claim 1 wherein the sewage transfer means comprises agrinder and an electrically operated valve, and conduit means isincluded to interconnect the grinder and valve between the separatingtank and the sewage receiving means.
 14. The system according to claim 1including: additional electrically operable sewage transfer meansconnected to the sewage receiving means for transferring sewagetherefrom to an ultimate point of disposal from the system; additionalelectrical circuit means operably connecting the additional sewagetransfer means to the first electrical circuit means so that itsoperation is initiated when the first electrical circuit means isactivated; further additional electrical circuit means operablyconnected to the additional sewage transfer means for continuing itsoperation after the first electrical circuit means is de-activated, andadditional sewage level sensing means in the sewage receiving meansoperably connected to the further additional electrical circuit meansfor de-activating it when the sewage receiving means has emptied to apredetermined level.
 15. The system according to claim 14 wherein: theadditional electrically operable transfer means comprises pump and valvemeans, and conduit means connecting the pump and valve means to thesewage receiving means near the bottom thereof.
 16. The system accordingto claim 14 wherein the additional level sensing means comprises a floatassembly positioned to operate when the sewage receiving means emptiesto a predetermined level.
 17. The system according to claim 14 whereinthe additional electrical circuit means comprises: an electrical Controlcircuit connected between the first electrical circuit means and theadditional sewage transfer means, an asymmetric electrical conductorconnected in the circuit so as to conduct current only from the firstelectrical circuit means to the additional electrical circuit means;normally open switch means closed by the additional sewage level sensingmeans when sewage reaches a predetermined level in the sewage receivingmeans; a source of electrical energy and an electrical relay includingan energization coil and a pair of normally open electrical contactsconnected serially to the normally open switch means whereby theadditional electrically operable sewage transfer means is''''locked-in'''' operation after the first electrical circuit means isde-activated and maintained in operation until the additional levelsensing means releases the closed normally open switch means after thesewage receiving means has emptied to a predetermined level.
 18. Thesystem according to claim 17 wherein the additional level sensing meansis a float positioned near the bottom of the sewage receiving means andmechanically connected to the normally open switch means to close itwhen sewage rises in the sewage receiving means causing the float torise above a normal rest position and to release the switch when thesewage level falls to a level corresponding to the normal float positionor below it.
 19. The system according to claim 1 including: fluidcirculation means including electrically operable pump means, fluidcirculation means, connected to the upper portion of the separating tankfor directing the fluid to a point of utilization.
 20. The systemaccording to claim 19 wherein: pressurized accumulator means is includedin the fluid circulation means; a normally open pressure operatedelectrical switch means is connected to the accumulator means forclosing when the pressure therein falls below a predetermined value;electrical circuit means connecting the switch means to a source ofelectrical energy and to the pump means of the fluid circulation meanswhereby additional fluid is pumped from the separating tank into thefluid circulation means when the pressure therein falls below thepredetermined value maintained by the pressure switch means.
 21. Thesystem according to claim 20 including check valve means positioned inthe fluid circulation means at a point between the pump means and theaccumulator means.
 22. The system according to claim 19 including filtermeans positioned at the fluid entrance to the fluid circulation meansand elsewhere therein for further separating sewage from the fluidbefore its reuse.
 23. A sewage disposal system for separating sewagefrom a flush medium so the medium can be reused with minimal loss,comprising: a non-aqueous liquid flush medium for receiving and carryingsewage, the flush medium having a specific gravity less than that ofwater; a separating tank having an inlet for receiving sewage carried bythe flush medium, the flush medium separating from the sewage afterentering the separating tank and floating above the sewage due to itsdifferent specific gravity, the sewage remaining in a lower portion ofthe separating tank; sewage receiving means for receiving sewage fromthe separating tank after its separation from the flush medium; sewagetransfer means connected to the separating tank for transferring thesewage from the separating tank to the sewage receiving means; meansoperably connected to the sewage transfer means for initiating itsoperation, and sewage level sensing means positioned in a lower portionof the separating tank and operably connected to the means foractivating it when the sewage reaches a predetermined level in the tankthereby initiating operation of the sewage transfer means and thetransfer of sewage from the separating tank to the sewage receivingmeans.